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/. 5. Robertson 241 Bull. B.O.C. 1995 115(4) First field observations on the Sidamo Lark Heteromirafra sidamoensis by Iain S. Robertson Received 7January 1995 The Sidamo Lark is an Ethiopian endemic previously known from two specimens, one collected less than 2 km south of Negele (5°20'N, 39°35'E) at 1450 m in Sidamo Province on 18 May 1968 (Erard 1975) and a second individual collected on 15 April 1974, 12 km southeast of Negele (Ash & Olson 1985). On 27 November 1974 Sandra Fisher, Michael Lambarth and myself searched for larks in an area of grassland with a few scattered low whistling thorns Acacia drepanolobium and other acacias about 6 km south ofNegele. The habitat looked very suitable for larks but we were unable to find any. The following morning we searched a more extensive area of similar grassland 13 km southeast of Negele at the junction of the Filtu and Arero tracks, where a brief snatch of a lark-like song was heard by ISR. A lark hovering about 4 m above the grass could not be relocated after it dropped into cover. OnMseLarching the similar habitat south of thejunction almost immediately saw a lark run across a patch of bare ground surrounded by taller grass. We converged on the spot and accidentally flushed at least four similar larks m which rose to a height ofabout 5 and hovered momentarily, uttering a short call, before dropping back into the grass. We soon located the original bird and obtained excellent views. I was able to watch the bird through 10 x 42 binoculars and through a x 25 tripod-mounted telescope at distances down to about 10 m. The light conditions were excellent and there was little wind. The bird was unfamiliar to me but it had a distinctive appearance and I confidently identified it as H. sidamoensis. Itwas later ascertained that this was the exact site where Ash found his birds (J. S. Ash in litt. 1994). General appearance and behaviour When crouched the bird had an almost quail-like appearance, due to the large rounded head and prominent eye together with the richly marked upperparts and rather short bill. When active it adopted a very upright stance, reminiscent of Isabelline Wheatear Oenanthe isabellinus. The bird was rather tame and confiding, taking little notice ofour small group. It was, however, very unobtrusive and impossible to see when it entered the taller patches of grass. It appears that the species crouches and remains motionless to avoid detection and also that when flushed it runs into the cover of tall grass after alighting. This unobtrusive behaviour is well known in the two other species in this genus (Archer & Godman 1961). Description The upperparts including the wing-coverts were richly patterned rufous with darker centres and pale huffish tips to the feathers /. 5. Robertson 242 Bull. B.O.C. 1995 115(4) producing a distinctive scaly and streaked appearance, contrasting with the nape which was pale greyish-buff with fine dark streaks, the streaking continuing onto the sides of the neck and upper breast. The crown was brown with dark streaks and whitish tips to the feathers forming fine scales; a narrow whitish median crown-stripe and whitish supercilium were present. The ear-coverts were rufous-brown and the lores pale buff. The throat was white, unstreaked, the breast huffish with fine dark streaks concentrated at the sides. The flanks were unstreaked warm-buff and the belly appeared pale buffish-white. The tail, lower breast and belly were wet from contact with dew on the grass and it was not possible to determine the colour nor the length of the outer tail feathers; however the tail appeared rather ragged, and this was also true of the birds which we flushed. The bill was yellowish-horn, rather short, with the culmen slightly decurved. The legs were dark straw coloured, appearing quite long and fairly robust. Despite the close range I was unable to make out the length of the hind claw. The dark eye appeared large, perhaps accentuated by the pale lores and supercilium. Calls The birds which flushed uttered a soft tswee-ee-eep at the point where they hovered before dropping back into the cover. Although I have no experience of the other members of the genus (Rudd's Lark H. ruddi and Archer's Lark H. archeri), I was struck by the similarities between H. sidamoensis and photographs ofH. ruddi; in particular the upright stance, prominent dark eye and rather stout bill. In Keith et al. 1992 two song types are described for H. ruddi; one of them, in which birds fly up from the grass, whistle plaintively and drop back into the grass, sounds very similar to the behaviour of the birds which we saw. I suspecHt that the song ofH. sidamoensis will be found to be similar to that of ruddi and that the 'flappeting' display flight . tentatively assigned to H. sidamoensis by Ash probably refers to another We species. did not, however, record any other species of lark in the immediate area of the grasslands. Remarks This is the first field observation of the species. It was looked for unsuccessfully at the type locality in October/November 1971 (Erard 1975) and again in March 1989 (Ash & Gullick 1989). The author visited the area in November 1989 but due to military activity it was not possible to search the grasslands. In November 1994 the military training camp had been removed, the airstrip was disused and there was little sign of human activity. The grasslands are no longer grazed by gazelles or oryx; these appear to have been extirpated, perhaps due to the military presence in the late 1980s. Local Borana people were grazing flocks of goats and cattle on the grassland but not in the immediate vicinity of the lark site. There had been prolonged rains in /. 5. Robertson 243 Bull. B.O.C. 1995 115(4) the wet season of 1994 resulting in a good growth of grass, though the habitat was beginning to dry out by the time of our visit. It would appear that suitable habitat still exists in the area and that the species has survived in these grasslands undetected, probably due to its unobtrusive habits and the fact that previous searches have been adversely affected by a combination of drought conditions and military activity. The species is treated as 'indeterminate' by Collar & Stuart (1985). This seems inconsistent with the treatment of two other species endemic to southern Ethiopia, White-tailed Swallow Hirundo megaensis and Stresemann's Bush-Crow Zavattariornis stresemanni, both ofwhich are treated as 'rare'. The ranges of these two species are considerably larger and contain a much greater area ofhabitat suitable for them. The extent of grassland habitat south of Negele would appear to be quite restricted by comparison. Both ofthe congeners ofH. sidamoensis have very restricted ranges, and Collar & Stuart considerHeteromirafra to be a threatened taxon. Acknowledgement I am most grateful to Dr J. S. Ash for commenting on a draft ofthis paper. References: Archer, G. F. & Godman, E. M. 1961. The Birds ofBritish Somaliland and the Gulfof Aden. Gurney & Jackson, London. Ash, J. S. & Gullick, T. M. 1989. Thepresentsituation regardingthe endemic breeding birds ofEthiopia. Scopus 13: 90-97. Ash, J. S. & Olson, S. L. 1985. A second specimen of Mirafra (Heteromirafra) sidamoensis Erard. Bull. Brit. Om. CI. 105: 141-143. Collar, X. J. & Stuart, S. N. 1985. Threatened Birds of Africa and Related Islands. ICBP/IUCX, Cambridge. Erard, C. 1975. Une nouvelle Alouette du sud de l'Ethiopie. Alauda 43: 115-124. Keith, S., Urban, E. K. & Fry, C. H. (eds) 1992. The Birds of Africa. Volume 4. Academic Press. Address: I. S. Robertson, Laurelbank, Exnaboe, Virkie, Shetland ZE3 9JS, U.K. t) British Ornithologists' Club 1995